Rake：当我尝试迁移时说表不存在......不，它不存在，这就是我尝试迁移的原因？

Question

命令和跟踪：

% rake db:migrate RAILS_ENV=test --trace
(in /Users/lprestonsegoiii/Work/GravityLabs/TinderBox)
** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
rake aborted!
Mysql::Error: Table 'project.medias' doesn't exist: SHOW FIELDS FROM `medias`
/Library/Ruby/Gems/1.8/gems/activerecord-2.3.8/lib/active_record/connection_adapters/abstract_adapter.rb:221:in `log'
/Library/Ruby/Gems/1.8/gems/activerecord-2.3.8/lib/active_record/connection_adapters/mysql_adapter.rb:323:in `execute'
/Library/Ruby/Gems/1.8/gems/activerecord-2.3.8/lib/active_record/connection_adapters/mysql_adapter.rb:470:in `columns'
/Library/Ruby/Gems/1.8/gems/activerecord-2.3.8/lib/active_record/base.rb:1301:in `columns'
/Library/Ruby/Gems/1.8/gems/activerecord-2.3.8/lib/active_record/base.rb:1314:in `column_names'
/Library/Ruby/Gems/1.8/gems/searchlogic-2.5.6/lib/searchlogic/named_scopes/ordering.rb:33:in `ordering_condition_details'
/Library/Ruby/Gems/1.8/gems/searchlogic-2.5.6/lib/searchlogic/named_scopes/ordering.rb:25:in `create_condition'
/Library/Ruby/Gems/1.8/gems/searchlogic-2.5.6/lib/searchlogic/named_scopes/or_conditions.rb:28:in `create_condition'
/Library/Ruby/Gems/1.8/gems/searchlogic-2.5.6/lib/searchlogic/named_scopes/column_conditions.rb:63:in `respond_to?'
/Library/Ruby/Gems/1.8/gems/activerecord-2.3.8/lib/active_record/base.rb:1511:in `respond_to?'
/Library/Ruby/Gems/1.8/gems/paperclip-2.4.0/lib/paperclip.rb:402:in `attachment_definitions'
/Library/Ruby/Gems/1.8/gems/paperclip-2.4.0/lib/paperclip.rb:283:in `has_attached_file'
/project/app/models/media.rb:23
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:158:in `require'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:158:in `require'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:265:in `require_or_load'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:425:in `load_missing_constant'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:80:in `const_missing'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:92:in `const_missing'
project/test/factories/general.rb:87  #This is where Media is referenced... but it should have errored about any of the other 10 Models that don't have tables above where this one is used in this file....
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:147:in `load_without_new_constant_marking'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:147:in `load'
/Library/Ruby/Gems/1.8/gems/factory_girl-2.0.5/lib/factory_girl/find_definitions.rb:20:in `find_definitions'
/Library/Ruby/Gems/1.8/gems/factory_girl-2.0.5/lib/factory_girl/find_definitions.rb:19:in `each'
/Library/Ruby/Gems/1.8/gems/factory_girl-2.0.5/lib/factory_girl/find_definitions.rb:19:in `find_definitions'
/Library/Ruby/Gems/1.8/gems/factory_girl-2.0.5/lib/factory_girl/find_definitions.rb:15:in `each'
/Library/Ruby/Gems/1.8/gems/factory_girl-2.0.5/lib/factory_girl/find_definitions.rb:15:in `find_definitions'
/Library/Ruby/Gems/1.8/gems/factory_girl-2.0.5/lib/factory_girl/rails2.rb:6
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:614:in `call'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:614:in `after_initialize'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:613:in `each'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:613:in `after_initialize'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:179:in `process'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:113:in `send'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/initializer.rb:113:in `run'
/project/config/environment.rb:17   #why does it jump into the env? this is irrelevant to raking.
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:156:in `require'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:156:in `require'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:521:in `new_constants_in'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:156:in `require'
/Library/Ruby/Gems/1.8/gems/rails-2.3.8/lib/tasks/misc.rake:4
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:636:in `call'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:636:in `execute'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:631:in `each'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:631:in `execute'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:597:in `invoke_with_call_chain'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_call_chain'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:607:in `invoke_prerequisites'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:604:in `each'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:604:in `invoke_prerequisites'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:596:in `invoke_with_call_chain'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_call_chain'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:583:in `invoke'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2051:in `invoke_task'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2029:in `top_level'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2029:in `each'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2029:in `top_level'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2023:in `top_level'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2001:in `run'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/bin/rake:31
/usr/bin//rake:19:in `load'
/usr/bin//rake:19

编辑： 第一个迁移文件： http://pastebin.com/49aJe2wv 它出错的表甚至还不存在。

测试数据库中没有表。

EDIT2：堆栈跟踪的详细信息 工厂/一般：87

Factory.define :media, :class => Media do |m| #line 87 <----
  m.name "Alice is in an asian wonderland"
  m.document_file_name "alice_test_image.jpeg"
  m.document_content_type "image/jpeg"
  m.document_file_size "155548"
...
end

编辑3： 媒体.rb http://pastebin.com/rZpdBTyq

Answer 1

这看起来像是您的工厂或factory_girl/factory_girl_rails 的问题。

factory_girl_rails 在启动时加载所有工厂，我认为如果它们包含关联、验证等，那么 ActiveModel/ActiveRecord 就会被调用来检查模型。当然，在这种情况下，他们发现没有数据库可供检查。

我遇到了同样的问题，解决方案/解决方法是删除 gem 'factory_girl_rails' 并将其替换为普通的 'factory_girl'，然后在 spec_helper 中手动加载工厂：

require 'factory_girl'
FactoryGirl.find_definitions

Answer 2

发生这种情况是因为您正在测试环境中运行 db:migrate 任务，并且您的工厂插件正在尝试加载尚不存在的表的模型：

/Users/lprestonsegoiii/Work/GravityLabs/TinderBox/test/factories/ General.rb:87

您应该在开发数据库上运行迁移，然后使用 db:test:prepare 克隆数据库进行测试：

rake db:migrate
rake db:test:prepare

Answer 3

首先，我们需要查看您的所有迁移。很可能您在创建迁移后删除了迁移或对其进行了修改，这会导致这种行为（或者如果您没有使用脚手架来生成迁移，那么您可能错误地编写了它们）。

在这种情况下，它可能尝试运行修改表的迁移，但在实际创建该表之前没有运行迁移，从而导致您看到的错误。